vc6到vc.net 错误

void CTrueColorToolBar::OnToolbarDropDown(NMHDR* pnmtb, LRESULT *plr)
{
 LPNMTOOLBAR pNMToolBar = reinterpret_cast<LPNMTOOLBAR>(pnmtb) ;

 for (int i = 0; i < m_lstDropDownButton.GetSize(); i++) {
  
  stDropDownInfo DropDownInfo = m_lstDropDownButton.GetAt(i);

  if (DropDownInfo.uButtonID == UINT(pNMToolBar->iItem)) {

   CMenu menu;
   menu.LoadMenu(DropDownInfo.uMenuID);
   CMenu* pPopup = menu.GetSubMenu(0);
   
   CRect rc;
   SendMessage(TB_GETRECT, (WPARAM)pNMToolBar->iItem, (LPARAM)&rc);
   ClientToScreen(&rc);
   
   pPopup->TrackPopupMenu(TPM_LEFTALIGN|TPM_LEFTBUTTON|TPM_VERTICAL,
                       rc.left, rc.bottom, DropDownInfo.pParent, &rc);
   break;
  }
 }
}